BrainKnowledge: A Human Brain Function Mapping Knowledge-Base System

Associating fMRI image datasets with the available literature is crucial for the analysis and interpretation of fMRI data. Here, we present a human brain function mapping knowledge-base system (BrainKnowledge) that associates fMRI data analysis and literature search functions. BrainKnowledge not only contains indexed literature, but also provides the ability to compare experimental data with those derived from the literature. BrainKnowledge provides three major functions: (1) to search for brain activation models by selecting a particular brain function; (2) to query functions by brain structure; (3) to compare the fMRI data with data extracted from the literature. All these functions are based on our literature extraction and mining module developed earlier (Hsiao, Chen, Chen. Journal of Biomedical Informatics 42, 912–922, 2009), which automatically downloads and extracts information from a vast amount of fMRI literature and generates co-occurrence models and brain association patterns to illustrate the relevance of brain structures and functions. BrainKnowledge currently provides three co-occurrence models: (1) a structure-to-function co-occurrence model; (2) a function-to-structure co-occurrence model; and (3) a brain structure co-occurrence model. Each model has been generated from over 15,000 extracted Medline abstracts. In this study, we illustrate the capabilities of BrainKnowledge and provide an application example with the studies of affect. BrainKnowledge, which combines fMRI experimental results with Medline abstracts, may be of great assistance to scientists not only by freeing up resources and valuable time, but also by providing a powerful tool that collects and organizes over ten thousand abstracts into readily usable and relevant sources of information for researchers.     

Mapping Underlying Maturational Changes in Human Brain

正Human brain development is a complex process that continues between birth and maturity,and monitoring the underlying maturational changes at these stages is crucial for our understanding of typical development as well as neurodevelopmental disorders.During the critical periods of brain development,on one hand,many human capacities originate,but on the other hand,a brain undergoing rapid     

fMRI:from Nuclear Spins to Brain Functions published

正fMRI:from Nuclear Spins to Brain Functions(ISBN:978-1-4899-7590-4,e Book ISBN:978-1-4899-7591-1)was published by Springer US in 2015.The editors of this book are Kamil Uludag(Maastricht Brain Imaging Centre,Maastricht University),Kamil Ugurbil(University of Minnesota School of Medicine)and Lawrence Berliner(Department of Chemistry and Biochemistry,University of Denver).This volume explores the revolutionary f MRI field from basic principles to state-of-the-art research.It covers a broad     

Brain plasticity in relapsing-remitting multiple sclerosis: evidence from resting-state fMRI

The purpose of this study is to investigate whether spontaneous brain activity amplitude alteration occurs in RRMS by comparing appropriately processed fMRI data from subjects with RRMS and healthy controls. Resting-state fMRIs collected from thirty-five RRMS patients and thirty-five age and sex-matched normal controls were compared to investigate the ALFF difference between the two groups. The relationships between ALFF in regions with significant group differences and the EDSS (Expanded Disability Status Scale), disease duration, T2 lesion volume were further explored. Our results showed that RRMS patients showed no regions with decreased ALFF, while showed significantly increased ALFF in the bilateral thalami, right insula (BA 13)/ right superior temporal gyrus (BA 22). The correlation between the EDSS and ALFF in the right insula/ right superior temporal gyrus was significant. From this study, we demonstrate that increased resting state amplitudes occur in the brain of patients with RRMS, specifically in areas with extensive cortical connections. We hypothesize that this is an adaptive phenomenon, reflecting either ongoing cortical plasticity in the resting-state, or increased neuronal activity related to coordination of remapped cortical functions.     

Functional Brain Reorganization in Multiple Sclerosis: Evidence from fMRI Studies

In patients with multiple sclerosis (MS), the severity of clinical signs is not closely related to indices of structural brain damage provided by conventional magnetic resonance MR. Accordingly, patients with MS may show symptom recovery while progressively accumulating tissue damage. Changes in functional organization of the cerebral cortex have been reported in functional magnetic resonance (fMRI) studies that have compared the activation patterns during motor, visual, and cognitive tasks of patients with MS with those of healthy controls. fMRI studies on MS have provided the results that are difficult to compare and may be discrepant because of differences in the criteria used for patient selection, the activation paradigm, the experimental design, and the MR acquisition parameters. Nevertheless, they do provide a new, interesting tool that sheds light on how the brain changes its functional organization in response to MS. In patients with MS, functional brain reorganization mainly consists of an increase in the extent of activation of the brain areas used by healthy subjects, as well as the recruitment of additional brain areas. These findings have been interpreted as adaptive or compensatory mechanisms that allow normal performance despite neural damage or loss. However, brain functional activity may also change in response to clinical disability, though the precise role of brain functional changes in MS has yet to fully understand. Longitudinal studies designed to explore the effects of both rehabilitation and pharmacological agents on brain plasticity might shed light on this issue.     

Human Genetics of Addiction: New Insights and Future Directions

Purpose of Review

With the advent of the genome-wide association study (GWAS), our understanding of the genetics of addiction has made significant strides forward. Here, we summarize genetic loci containing variants identified at genome-wide statistical significance (P?<?5?×?10^?8) and independently replicated, review evidence of functional or regulatory effects for GWAS-identified variants, and outline multi-omics approaches to enhance discovery and characterize addiction loci.

Recent Findings

Replicable GWAS findings span 11 genetic loci for smoking, eight loci for alcohol, and two loci for illicit drugs combined and include missense functional variants and noncoding variants with regulatory effects in human brain tissues traditionally viewed as addiction-relevant (e.g., prefrontal cortex [PFC]) and, more recently, tissues often overlooked (e.g., cerebellum).

Summary

GWAS analyses have discovered several novel, replicable variants contributing to addiction. Using larger sample sizes from harmonized datasets and new approaches to integrate GWAS with multiple ‘omics data across human brain tissues holds great promise to significantly advance our understanding of the biology underlying addiction.

     

Big Brain Data: On the Responsible Use of Brain Data from Clinical and Consumer-Directed Neurotechnological Devices

Neuroethics - The focus of this paper are the ethical, legal and social challenges for ensuring the responsible use of “big brain data”—the recording, collection and analysis of...     

Temporo-parietal dysfunction in Tourette syndrome: Insights from an fMRI study of Theory of Mind

Tourette syndrome (TS) is a neurodevelopmental disorder characterized by tics, repetitive movements and vocalizations which are prompted by a sensory-cognitive premonitory urge. Complex tics include environmentally dependent social behaviors such as echoing of other people's speech and actions. Recent studies have suggested that adults with TS can show differences to controls in Theory of Mind (ToM): reasoning about mental states (e.g. beliefs, emotions). In this study, twenty-five adults with uncomplicated TS (no co-morbid disorders, moderate tic severity), and twenty-five healthy age and gender matched controls were scanned with fMRI during an established ToM task. Neural activity was contrasted across ToM trials involving reasoning about false-belief, and matched trials requiring judgments about physical states rather than mental states. Contrasting task conditions uncovered differential fMRI activation in TS during ToM involving the right temporo-parietal junction (TPJ), right amygdala and posterior cingulate. Further analysis revealed that activity within the right TPJ as localised by this task covaried with the severity of symptoms including echophenomena, impulse control problems and premonitory urges in TS. Amygdala activation was also linked to premonitory urges, while activity in the left TPJ during ToM was linked to ratings of non-obscene socially inappropriate symptoms. These findings indicate that patients with TS exhibit atypical functional activation within key neural substrates involved in ToM. More generally, our data could highlight an important role for TPJ dysfunction in driving compulsive behaviors.     

Eyes-Open/Eyes-Closed Dataset Sharing for Reproducibility Evaluation of Resting State fMRI Data Analysis Methods

The multi-scan resting state fMRI (rs-fMRI) dataset was recently released; thus the test-retest (TRT) reliability of rs-fMRI measures can be assessed. However, because this dataset was acquired only from a single group under a single condition, we cannot directly evaluate whether the rs-fMRI measures can generate reproducible between-condition or between-group results. Because the modulation of resting state activity has gained increasing attention, it is important to know whether one rs-fMRI metric can reliably detect the alteration of the resting activity. Here, we shared a public Eyes-Open (EO)/Eyes-Closed (EC) dataset for evaluating the split-half reproducibility of the rs-fMRI measures in detecting changes of the resting state activity between EO and EC. As examples, we assessed the split-half reproducibility of three widely applied rs-fMRI metrics: amplitude of low frequency fluctuation, regional homogeneity, and seed-based correlation analysis. Our results demonstrated that reproducible patterns of EO-EC differences can be detected by all three measures, suggesting the feasibility of the EO/EC dataset for performing reproducibility assessment for other rs-fMRI measures.     

fMRI:From Nuclear Spins to Brain Functions published

正fMRI:From Nuclear Spins to Brain Functions(ISBN:978-1-4899-7590-4,e Book ISBN:978-1-4899-7591-1)was published by Springer US in 2015.The editors of this book are Kamil Uludag(Maastricht Brain Imaging Centre,Maastricht University),Kamil Ugurbil(University of Minnesota School of Medicine)and Lawrence Berliner(Department of Chemistry and Biochemistry,University of Denver).     

Mapping hemodynamic correlates of seizures using fMRI: A review

Functional magnetic resonance imaging (fMRI) is able to detect changes in blood oxygenation level associated with neuronal activity throughout the brain. For more than a decade, fMRI alone or in combination with simultaneous EEG recording (EEG‐fMRI) has been used to investigate the hemodynamic changes associated with interictal and ictal epileptic discharges. This is the first literature review to focus on the various fMRI acquisition and data analysis methods applied to map epileptic seizure‐related hemodynamic changes from the first report of an fMRI scan of a seizure to the present day. Two types of data analysis approaches, based on temporal correlation and data driven, are explained and contrasted. The spatial and temporal relationship between the observed hemodynamic changes using fMRI and other non‐invasive and invasive electrophysiological and imaging data is considered. We then describe the role of fMRI in localizing and exploring the networks involved in spontaneous and triggered seizure onset and propagation. We also discuss that fMRI alone and combined with EEG hold great promise in the investigation of seizure‐related hemodynamic changes non‐invasively in humans. We think that this will lead to significant improvements in our understanding of seizures with important consequences for the treatment of epilepsy. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.     

Activation of the Brain to Postpone Dementia: A Concept Originating from Postmortem Human Brain Studies

Alzheimer's disease(AD) is characterized by decreased neuronal activity and atrophy, while hyperactivity of neurons seems to make them resistant to aging and neurodegeneration, a phenomenon which we have paraphrased as ‘use it or lose it'. Our hypothesis proposes that(1) during their functioning, neurons are damaged;(2)accumulation of damage that is not repaired is the basis of aging;(3) the vulnerability to AD is determined by the genetic background and the balance between the amount of damage and the efficiency of repair, and(4) by stimulating the brain, repair mechanisms are stimulated and cognitive reserve is increased, resulting in a decreased rate of aging and risk for AD. Environmental stimulating factors such as bilingualism/multilingualism, education, occupation, musical experience, physical exercise, and leisure activities have been reported to reduce the risk of dementia and decrease the rate of cognitive decline, although methodological problems are present.     

Brain activity in bilingual developmental dyslexia: an fMRI study

The aim of this study was to identify the neural substrates of an adult English-German bilingual with dyslexia (in both languages) during lexical decision-making using functional magnetic resonance imaging (fMRI). A lexical decision task with five conditions in a block design was employed (nonverbal shape judgment, lettercase judgment, regular word judgment, irregular word judgment, and nonword judgment), and the activation was compared to a non-dyslexic control bilingual and a control monolingual participant. Both of the control participants matched the dyslexic bilingual BK on age, sex, IQ, handedness, and education level. Results indicated that the bilingual adult with dyslexia was strongly right lateralized for stimuli that required phonological processing, a profile that differed particularly from the activation observed from the monolingual participant. These results are consistent with the idea of increased activation (mostly in the right hemisphere) during linguistic tasks in adults with dyslexia and in late proficient bilinguals relative to monolinguals. Findings also suggest that the additional activation observed in both of the bilinguals are similar, suggesting that these effects are not additive in the dyslexic bilingual.     

Cortical Malformations and Epilepsy: New Insights from Animal Models

In the last decade, the recognition of the high frequency of cortical malformations among patients with epilepsy especially children, has led to a renewed interest in the study of the pathophysiology of cortical development. This field has also been spurred by the recent development of several experimental genetic and non-genetic, primarily rodent, models of cortical malformations. Epileptiform activity in these animals can appear as spontaneous seizure activity in vivo, in vitro hyperexcitability, or reduced seizure susceptibility in vitro and in vivo. In the neonatal freeze lesion model, that mimics human microgyria, hyperexcitability is caused by a reorganization of the network in the borders of the malformation. In the prenatal methylazoxymethanol model, that causes a diffuse cortical malformation, hyperexcitability is associated with alteration of firing properties of discrete neuronal subpopulations together with the formation of bridges between normally unconnected structures. In agreement with clinical evidence, these experimental data suggest that cortical malformations can both form epileptogenic foci and alter brain development in a manner that causes a diffuse hyperexcitability of the cortical network.     

Recent Advances in the Genetics of Epilepsy: Insights from Human and Animal Studies

Progress in understanding the genetics of epilepsy is proceeding at a dizzying pace. Due in large part to rapid progress in molecular genetics, gene defects underlying many of the inherited epilepsies have been mapped, and several more are likely to be added each year. In this review, we summarize the available information on the genetic basis of human epilepsies and epilepsy syndromes, and correlate these advances with rapidly expanding information about the mechanisms of epilepsy gained from both spontaneous and transgenic animal models. We also provide practical suggestions for clinicians confronted with families in which multiple members are afflicted with epilepsy.     

Dynamic Changes of the Mitochondria in Psychiatric Illnesses: New Mechanistic Insights From Human Neuronal Models

Mitochondria play a crucial role in neuronal function, especially in energy production, the generation of reactive oxygen species, and calcium signaling. Multiple lines of evidence have suggested the possible involvement of mitochondrial deficits in major psychiatric disorders, such as schizophrenia and bipolar disorder. This review will outline the current understanding of the physiological role of mitochondria and their dysfunction under pathological conditions, particularly in psychiatric disorders. The current knowledge about mitochondrial deficits in these disorders is somewhat limited because of the lack of effective methods to dissect dynamic changes in functional deficits that are directly associated with psychiatric conditions. Human neuronal cell model systems have been dramatically developed in recent years with the use of stem cell technology, and these systems may be key tools for overcoming this dilemma and improving our understanding of the dynamic changes in the mitochondrial deficits in patients with psychiatric disorders. We introduce recent discoveries from new experimental models and conclude the discussion by referring to future perspectives. We emphasize the significance of combining studies of human neuronal cell models with those of other experimental systems, including animal models.